Suspendable refractory unit



United States Patent O 3,234,703 SUSPENDABLE REFRACTORY UNIT William Arthur Sullivan, Jr., Cartierville, Quebec, Canada, assignor to Kaiser Aluminum & Chemical Corporation, Oakland, Calf., a corporation of Del-aware Filed Jan. 31, 1963, Ser. No. %5,294 2 Claims. (Ci. 52-509) This invention rel ates to refractory blocks or bricks for use in the roofs of furnaces operated at high temperatures, especially metallurgical furnaces; and in particular it relates to a hanger brick or Suspended brick and to means for suspending the same, and to such brick and means forming a suspension assembly.

During the operation of high temperature furnaces, roof bricks spall, erode or peel away at the hot face, i.e. the surface exposed to the heat, under the influences of rapid fluctuations in temperature, eg., upon charging fresh feed to such furnaces, or due to the erosive action of furnace gases or Chemical attack. It then becomes necessary to remove and replace the more badly worn brick and to replace them or a few of them, perhaps over only a limited area of the furnace roof. It is desirable to maintain the furnace in operation and to replace such brick by insertion and suspension from above. It is especially desirable that the means for suspension be simple and economical, and also that it be of such character and placement that it is not exposed directly to the high temperatures and erosive atmosphere of the furnace.

Many devices have been pro posed for suspending refractory blocks and many blocks have been designed for the production or repair of furnace roofs. In general, the design of the hanger device has been complex and expensive to fabricate, or has required at least a partial metal casing on the brick or molding into the brick itself at the time of its formaton. In many instances, packing the bricks With the hanger means attached has raised serious shipping problems.

In accordance with the present invention, there is provided a refractory brick or block having a recess ad'apted to receive a hanger device, and a simple hanger device which is adapted to be inserted into such recess at the place of use to enable suspension of such block, eg., by engagement with known hanger device in a metallurgical furnace roof. The blocks and hanger means can be shipped separately in a simple and economical manner, and easily assembled at the time and place of use.

According to the present invention, there is provided a suspendible refractory brick and a simple, economical suspension means which firmly holds the brick and at the same time per-mits suspension thereof, eg., in hot patching a furnace roof, without the concomitant necessity of metal-plating such brick.

The brick and suspension means, tberefore, are illustrated in the drawings, wherein:

FIGURE 1 is a front elevation view of the brick with suspension means in place;

FIGURE 2 is a perspecitve View of the brick and of the suspension means in place in the brick;

FIGURE 3 is a perspective view of the suspension means;

FIGURE 4 is a vertical sectional View of the embodiment of FIGURE 1, taken online 4-4;

FIGURE 5 is a vertical sectional vieW of another embodiment of the invention.

The refractory block 10, which can be made of any desired refractory material, for example, a magnesite chrome or chrome magnesite composition known to the art, has four side faces, three of which are shown at 18, 19 and 20, and end faces 21, which is the top face, and 22, which is the bottom or hot face, the l-atter being exposed to the heat of the furance when the brick is installed in a furnace roof. Extending inwardly from one side face of the brick, at the upper portion thereof, to approximately the central portion thereof is a recess 13 having a 'base 11 and side walls 14 which converge to form a narrow aperture at the upper face 21 of block 10, forming in one embodiment a slot in the upper portion of the brick having a cross section transverse to its axis in the form generally of .a trapezoid of which the narrower top side is the width of the opening in the top face of the brick, the wider bottom is the width of the base of the slot and the nonparallel walls are the upwardly converging side surfaces of the slot. Preferably, the cross-section of the slot is in the form of an isosceles trapezoid.

The separately provided hanger element 12, which is a narrow strip or band of steel, includes a resilient, or springing, open loop 17 adapted to be inserted into the recess 13 of brick 10, and an elongated hanger extension 16 at one end of such loop. At the opposite end of loop 17 from hanger extension 16 there is a divergent extension 15 which permits grasping contracting and easy insertion of loop 17 into recess 13. Suitably, the suspension element 12 is 'a strip of high tension, or high tensile, low alloy steel or stainless steel and it is preferably from about Mi to /2 inch in width.

As shown in FIGURE 3, extension 16, which includes an aperture 23 to permit hanging to a supporting device, for instance in the furnace roof, and extension 15 are grasped by the operator and pressed toward each other as shown in phantom in FIGURE 3. As the loop 17 is contracte-d under this pressure, it can be inserted into recess 13 where the bottom of the loop will rest on or adjacent to base 11 of recess 13 and will be placed at the end 24 of recess 13. As the pressure on extensions 15 and 16 is released by the w'orker, the loop springs back against converging walls 14 of recess 13 and the hanger device 12 is firmly retained within recess 13. can be seen that insertion of the hanger is greatly facilitated and the patching or construction of a roof, using the device of this invention, can be carried out m a simple, rapid and economical manner. The loop 17 of device 12 having a configuration approxmately that of the transverse section of the recess 13 frictionally engages side walls 14 of the recess 13 thus avoiding dsplacement during installation and handling of the brick. The suspension device 12 is suitably made of ferrous metal but preferably it is made of stainless steel n order to resist the destructive efiect of the heat at the furnace roof.

In the embodiment shown in FIGURE 5, there is provided a slot 26 in a brick 28, wherein the bottom face or base of slot 26 is inclined upwardly toward its closed end 29 at about the central axis of the brick. Otherwise, the brick is substantially the same as the brick shown in the remaining figures and like numerals indicate like elements. In the embodiment of FIGURE 5, however, the upwardly inclined slot base enables easier formation in a dry press; and it further ensures the secure retention of the hanger strip and loop in the slot or recess because the loop 17, which springs against sides 14, also tends to press more firmly, upon hanging, against the end 29 of recess 26.

It will be apparent that the refractory block of the particular Construction herein described and the suspension means enable rapid patching of a furnace roof, for example, to replace brick which have been eroded away during operation of the furnace. It will also be understood that the slot and its end face may be displaced to one side or the other of a central -or central axis location, e.g., if it be desired that the brick or block be disposed at an angle or off-center in a roof. Other modifications and variations in the article of this invention 3 can be made without departing from the spirit and scope of the claims. For instance, the hanger extension can be looped or hooked for installation, if desired. Also, the metallic hanger element can be formed of a wire or rod, having a loop portion which is adapted to springing contact within a recess in a brick as described hereinabove. If desired, the brick can also be provided with internal or external plating, or with both. The brick recess can be other than trapezoidal so long as the sides converge to a narrow opening at the top and the slot is adapted to receive a hanger element in springing contact, as described herein, to support the brick weight. For instance, a slot of substantially circular cross-section open at the upper portion of one face of the brick and providing a narrow aperture extending from the side face to about the central portion of the brick at the top face thereof, could be employed; but for best strength the trapezoidal configuration is preferred.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. An assembly for suspension in a high temperature furnace roof comprising a refractory block having four side faces, a top face and a bottom face, and having a recess of trapezoidal transverse section extending inwardly from the top portion of a side face thereof to approximately the md section of said block and having side walls converging toward the top face of said block, the top face of said block having a narrow aperture extending inwardly from a side face and communicating with said recess; and a resilient, upwardly open loop of high tensile steel strap having exteriorly disposed free ends, said loop having a configuration approximating that of the transverse section of said recess and being disposed within said recess in springing contact with said converging side walls, one free end of said looped strap extending above the top face of said block and being adapted to suspend said assembly and the other free end of said looped strap divergently extending above the top face of said block to enable grasping and' contracting said loop for its inserton in said 'ecess.

2. An assembly for suspension in a high temperature furnace roof comprising a refractory block having four side faces, a top face and a bottom face, and having a recess of trapezoidal transverse section extending inwardly from the top portion -of a side face thereof to approximately the md section of said block and having side walls converging toward the top face of said block, the base of said recess being inclined upwardly toward the central aXis of said block, the top face of said block having a narrow aperture extending inwardly from a side face and communicating with said recess; and a resilient, upwardly References Cited by the Examiner UNITED STATES PATENTS 496,544 !5/ 1893 Strusholm -420 1,076,240 10/ 1913 Schuffenhauer 50-61 1,506,45 8 8/ 1924 Strachota -99 1,708,696 4/1929 Hellerman 50-468 1,772,797 8/1930 Butz 110-99 1,805,538 5/1931 Anderberg 50 -401 2,066,205 12/1936 Keating 50-401 2,089,046 8/1937 Venzie 50-401 3,ll4,220 12/1963 Maddox et al 50 398 FOREIGN PATENTS 969,()43 5/ 1950 France. 1,278,173 10/1961 France.

927,632 5/1963 Great Britain.

56,074 5/ 1911 Switzerland.

FRANK L. ABBOTT, Prmary Examiner.

HENRY C. SUTHERLAND, JACOB L. NACKENOFF,

Exam'ners. 

1. AN ASSEMBLY FOR SUSPENSION IN A HIGH TEMPERATURE FURNACE ROOF COMPRISING A REFRACTORY BLOCK HAVING FOUR SIDE FACES, A TOP FACE AND A BOTTOM FACE, AND HAVING A RECESS OF TRAPEZOIDAL TRANSVERSE SECTION EXTENDING INWARDLY FROM THE TOP PROTION OF A SIDE FACE THEREOF TO APPROXIMATELY THE MID SECTION OF SAID BLOCK AND HAVING SIDE WALLS CONVERGING TOWARD THE TOP FACE OF SAID BLOCK, THE TOP FACE OF SAID BLOCK HAVING A NARROW APERTURE EXTENDING INWARDLY FROM A SIDE FACE AND COMMUNICATING WITH SAID RECESS; AND A RESILIENT, UPWARDLY OPEN LOOP OF HIGH TENSILE STEEL STRAP HAVING EXTERIORLY DISPOSED FREE ENDS, SAID LOOP HAVING A CONFIGURATION APPROXIMATING THAT OF THE TRANSVERSE SECTION OF SAID RECESS AND BEING DISPOSED WITHIN SAID RECESS IN SPRINGING CONTACT WITH SAID CONVERGING ABOVE WALLS, ONE FREE END OF SAID LOOPED STRAP EXTENDING ABOVE THE TOP FACE OF SAID BLOCK AND BEINGING ADAPTED TO SUSPEND SAID ASSEMBLY AND THE OTHER FREE END OF SAID LOOPED STRAP DIVERGING EXTENDING ABOVE THE TOP FACE OF SAID BLOCK TO ENABLE GRASPING AND CONTRACTING SAID LOOP FOR ITS INSERTION IN SAID RECESS. 